If you need to generate test samples in different YUV formats you can use GStreamer's ffmpegcolorspace plugin like in the following snippet; for instance, in order to get an image in the NV12 raw format you can do:

In Debian Unstable the transition to Gnome 3 is taking place; when Gnome 3.0 firstly came out some unnamed geeky users complained loudly about the design decisions of the development team to push strongly towards gnome-shell as a new defaultUI; gnome-shell was designed focusing on usability (usability is a metric relative to a certain target audienceBTW) and simplicity, hiding a lot of details from the users. Obviously you can never make everyone happy so some of us simply happened to be “out of target”: you know us computer people (*cough cough*), we like to be in charge and control The Machine...